CN116495609B - A crane spreader with a swing angle detection device - Google Patents

Abstract

This application provides a crane sling with a swing angle detection device, which includes an upper platform, a rigid connecting rod, four angle adjustment cables, four lifting motors, a lower platform, a CCD camera and a level; by connecting the upper platform and the lower platform A rigid connecting rod with a spherical hinge ball head is designed between them. The rigid connecting rod not only provides rigid support, but also can adjust the attitude of the lower platform, thereby driving the object to be hoisted fixed below it to adjust the attitude. To complete the It provides convenience for final assembly; the CCD camera can detect the posture of monocular vision, and feedback controls the lifting motor to adjust the posture of the lower platform, which improves the integration and reliability of the spreader and achieves good technical results.

Description

A crane spreader with a swing angle detection device

Technical field

This application relates to the technical field of crane spreader adjustment, specifically to a crane spreader with a swing angle detection device. The spreader is suitable for hoisting objects that require attitude adjustment, and is especially suitable for various fields such as chemical industry, aviation, aerospace, weapons, etc. Lifting of large non-standard parts.

Background technique

Large piece lifting is the operation process of moving large pieces from the original position to another position through lifting equipment. At present, common technical solutions in the industry can only achieve horizontal lifting and translation of the lifting target object. They cannot complete multi-angle lifting, nor can they stably adjust and maintain the posture of the target object during the lifting movement, which is convenient for subsequent installation of the workpiece. and debugging convenience.

In the existing technology, the above-mentioned posture adjustment and maintenance often need to be completed manually by workers on site. However, since the hoisting slings are often flexible (steel ropes or chains), the actual operation of this work is time-consuming and laborious, and even after adjustment, the accuracy is difficult to maintain. And there are serious safety hazards (such as workpiece falling and injuring people or workpiece being damaged by collision, etc.). For example, in the aerospace field, the docking process of a certain model of aerospace return device's heat-proof roof (used to resist the high-temperature ablation of the return device by the atmosphere during the return process) and the capsule, from lifting to installation, requires the establishment of an electronic theodolite site or The total station performs large-scale precision measurements. This process requires repeated measurements and iterative adjustments. It takes about a day to achieve the final result that meets the requirements.

To sum up, the existing technology mainly has the following problems: (1) Traditional spreaders cannot adjust the attitude of the workpiece, resulting in extended assembly time; (2) Even if the attitude adjustment of the workpiece is manually completed with traditional spreaders, it is difficult to adjust the attitude of the workpiece. To maintain this state stably, the movement of the lifting equipment will often cause large deviations.

Therefore, it is very necessary to provide a crane spreader with a swing angle detection device to adapt to the hoisting of objects that require attitude adjustment.

Contents of the invention

In order to make up for the above shortcomings, this application provides a crane spreader with a swing angle detection device.

This application relates to a crane sling with a swing angle detection device, which can provide rigid support for objects to be hoisted. On this basis, the attitude adjustment of the objects to be hoisted is realized through flexible steel cables, providing a solid foundation for subsequent final assembly. Basically, the swing angle detection device can ensure the accuracy of the attitude of the object to be hoisted.

This application adopts the following technical means to achieve this.

A crane spreader with a swing angle detection device includes.

Height adjustment mechanism, rotating mechanism, upper platform, rigid link, four angle adjustment cables, four lifting motors, lower platform, CCD camera, target ruler and level.

The upper end of the height adjustment mechanism is fixedly connected to the lower end of the trolley mechanism of the lifting device, the lower end of the height adjustment mechanism is fixedly connected to the fixed part of the rotating mechanism, and the rotating part of the rotating mechanism is fixedly connected to the center position of the top surface of the upper platform; the rigid connecting rod The upper end is fixedly connected to the center of the bottom surface of the upper platform. The lower end of the rigid connecting rod is equipped with a lower spherical hinge ball head. The lower spherical hinge ball head at the lower end of the rigid connecting rod is built into the lower platform. The rigid connecting rod passes through the lower spherical hinge ball head. The lower platform provides a rigid support, and the lower platform can realize rotation angle adjustment by relying on the lower ball hinge ball head provided on it.

Both the upper platform and the lower platform are square structures. Each of the four inner corners of the upper platform is equipped with a lifting motor; the lower ends of the four angle adjustment cables are respectively connected to the four end corners of the upper surface of the lower platform, and their upper ends are connected to their corresponding The output shaft of the lifting motor in the upper platform and the four angle adjustment cables are equipped with tension sensors; the tension sensors are used to monitor the amount of tension exerted by the angle adjustment cables; during the driving process of the angle adjustment cables, if the tension If the value of the sensor exceeds the first threshold, the lift motor corresponding to the angle adjustment cable will reduce its speed. If the value of the tension sensor exceeds the second threshold, the lift motor corresponding to the angle adjustment cable will stop immediately. The second threshold is greater than the first threshold.

A CCD camera is provided on the lower surface of the upper platform, a target ruler opposite to the CCD camera is provided on the upper surface of the lower platform, and a level is also provided on the lower platform; the CCD camera, target ruler and level form a swing angle detection device to realize the lower platform Swing angle detection.

The lower surface of the lower platform is provided with a number of T-shaped slots and threaded holes in an array, which are used to fix special spreaders for clamping and hoisting objects. The special spreaders are used to determine the initial posture of the hoisted objects.

Preferably, the target ruler is an isosceles right triangle, with a total of four targets arranged on it. The distance between the targets is known. Three targets are arranged at equal intervals on the hypotenuse, and there are two targets on each right-angled side.

Preferably, the height adjustment mechanism is a hydraulic cylinder, a pneumatic cylinder or an electric push rod.

Preferably, the rotating mechanism is an electric turntable.

Preferably, four cable guide mechanisms are provided at the lower middle position of the rigid connecting rod. The angle adjustment cable passes through the cable guide mechanism and is connected to the output shaft of the corresponding lifting motor in the upper platform.

Preferably, the cable guide mechanism is a guide pulley with a rotating shaft fixed at a lower middle position of the rigid link.

Preferably, a guide pulley is provided on the lower surface of the upper platform to adjust the direction of the angle adjustment cable.

On the other hand, this application also discloses a crane spreader with a swing angle detection device, including:

Height adjustment mechanism, rotating mechanism, upper platform, rigid link, four angle adjustment cables, four lifting motors, lower platform, CCD camera, projector and level.

The upper end of the height adjustment mechanism is fixedly connected to the lower end of the trolley mechanism of the lifting device, the lower end of the height adjustment mechanism is fixedly connected to the fixed part of the rotating mechanism, and the rotating part of the rotating mechanism is fixedly connected to the center position of the top surface of the upper platform; the rigid connecting rod is connected to The center position of the upper platform is connected through an upper spherical hinge ball head provided at the upper end of the rigid connecting rod. The upper spherical hinge ball head of the rigid connecting rod is built into the upper platform. The lower end of the rigid connecting rod is fixedly connected to the center position of the upper surface of the lower platform. The rigid connecting rod is The connecting rod provides a rigid support for the lower platform, and the rotation angle of the lower platform can be adjusted through the upper ball joint.

Both the upper platform and the lower platform are square structures. Each of the four internal corners of the upper platform is equipped with a lifting motor; the lower ends of the four angle adjustment cables are respectively connected to the four end corners of the upper surface of the lower platform, and are connected to the rigid connecting rods. Four steel cable guide mechanisms are set at the lower part of the middle. The angle adjustment cables pass through the cable guide mechanisms and are connected to the output shaft of the corresponding lifting motor in the upper platform; the four angle adjustment cables are driven by the four lifting motors. The angle of the lower platform can be adjusted flexibly; the four angle adjustment cables are equipped with tension sensors.

A cavity for accommodating the upper ball hinge ball head is formed in the lower part of the upper platform, and a tapered hole with a larger upper and smaller size is formed in the lower part of the cavity; a cylindrical cavity is formed in the upper part of the cavity, and a cylindrical cavity is formed in the lower part of the cavity. On the upper part, a CCD camera and a projector are fixed on the inner side of the upper wall of the upper platform; a part of the top of the upper spherical hinge ball head is cut off to form a target surface parallel to the lower platform. If the height of the cut-off part is not greater than the diameter of the sphere, the projector can be Project target points on the target surface.

The CCD camera, projector and level form a swing angle detection device to realize the swing angle detection of the lower platform.

Preferably, during the driving process, if the value of the tension sensor exceeds the first threshold, the lifting motor corresponding to this angle adjustment cable will operate at a reduced speed; if the value of the tension sensor exceeds the second threshold, the lift motor corresponding to this angle adjustment cable will operate at a reduced speed. The lifting motor corresponding to the adjustment cable will stop immediately, and the second threshold is greater than the first threshold.

The lower surface of the lower platform is provided with a number of T-shaped slots and threaded holes in an array, which are used to fix special slings for clamping and hoisting objects; the special slings ensure the initial posture of the hoisted objects.

Compared with the prior art, this application has the following advantages.

(1) Crane spreaders in the prior art are generally rigid spreaders designed for specific products or ordinary wire rope flexible spreaders, and do not have the function of attitude adjustment. In this application, a belt is designed between the upper platform and the lower platform. There is a rigid connecting rod with a spherical hinge ball head. The rigid connecting rod not only provides rigid support, but also can adjust the attitude of the lower platform, thereby driving the object to be hoisted fixed below it to adjust the attitude.

(2) By setting up a height adjustment mechanism, a rotating mechanism, a rigid connecting rod, and four angle adjustment cables, angle and displacement adjustments in multiple dimensions can be achieved, and the posture of the object to be hoisted can be adjusted efficiently, thereby achieving rapid assembly.

(3) The spreader can realize timely detection of posture by combining the posture detection device with monocular vision, and feedback controls the lifting motor to adjust the posture; the swing angle detection scheme is compared with other existing inertial components (gyros). and/or accelerometer) solution or the use of other optical angle sensor solutions effectively reduces costs and achieves good application results while meeting accuracy requirements. The principle is simple and intuitive, and is very suitable for use by on-site workers.

(4) Four steel cable guide mechanisms are installed at the lower middle part of the rigid connecting rod, which is equivalent to lowering the position of the fixed end of the steel cable, which can effectively improve the stability of the lower platform.

(5) The technical solution of placing the CCD camera and projector in the upper platform can effectively avoid the fixed deformation of the target ruler and the influence of its own thermal expansion coefficient. The CCD camera is placed inside the cavity, which can effectively avoid the interference of the external environment on the CCD camera. ;Further improve the integration and reliability of the spreader and achieve better technical results.

Description of drawings

Figure 1 shows a schematic structural diagram of a crane spreader with a swing angle detection device.

Figure 2 shows the structural diagram of the target ruler.

FIG. 3 is a schematic structural diagram of another embodiment of the crane spreader with a swing angle detection device shown in FIG. 1 .

Figure 4 shows a schematic structural diagram of another embodiment of a crane spreader with a swing angle detection device.

Figure 5 shows a schematic structural diagram of the upper spherical hinge structure and the swing angle detection device.

Figure 6 shows the working diagram of the control unit.

The reference numbers are as follows.

1-height adjustment mechanism, 2-rotating mechanism, 3-upper platform, 4-rigid link, 5-lower platform, 6-angle adjustment cable, 7-lift motor, 8-tension sensor, 9-CCD camera, 10 -Target ruler, 11-level, 12-T-shaped slot, 13-cable guide mechanism, 14 lower ball hinge ball head, 15-upper ball hinge ball head, 16-projector, 31-cone hole, 32-cavity , 151-target surface.

Detailed ways

The present application will be further described in detail below in conjunction with the accompanying drawings and examples. It can be understood that the specific embodiments described here are only used to explain the present application, but not to limit the present application. In addition, it should be noted that, for convenience of description, only some but not all parts relevant to the present application are shown in the drawings.

Embodiment 1

As shown in Figure 1, a crane spreader 100 with a swing angle detection device includes: a height adjustment mechanism 1, a rotating mechanism 2, an upper platform 3, a rigid connecting rod 4, four angle adjustment cables 6, and four lifting motors 7 , lower platform 5, CCD camera 9, target ruler 10, level 11.

The upper end of the height adjustment mechanism 1 is fixedly connected to the lower end of the trolley mechanism of the lifting device, the lower end of the height adjustment mechanism 1 is fixedly connected to the fixed part of the rotating mechanism 2, and the rotating part of the rotating mechanism 2 is fixedly connected to the center position of the top surface of the upper platform 3 The upper end of the rigid connecting rod 4 is fixedly connected to the center of the bottom surface of the upper platform 3. The lower end of the rigid connecting rod 4 is provided with a lower ball hinge ball head 14. The lower ball hinge ball head 14 at the lower end of the rigid connecting rod 4 is built into the lower platform 5. Inside, the rigid connecting rod 4 provides a rigid support for the lower platform 5 through the lower spherical hinge ball head 14, and the lower platform 5 can realize rotation angle adjustment by relying on the lower spherical hinge ball head 14 provided thereon.

Both the upper platform 3 and the lower platform 5 are square structures with a certain thickness. Each of the four internal corners of the upper platform 3 is provided with a lifting motor 7; the lower ends of the four angle adjustment cables 6 are respectively connected to the upper surface of the lower platform 5. The upper ends of the four end corners are connected to the output shafts of the corresponding lifting motors 7 in the upper platform 3 . The four angle adjustment cables 6 can flexibly adjust the angle of the lower platform 5 through the driving of the four lifting motors 7 . The four angle-adjusting steel cables 6 are each provided with tension sensors 8. The tension sensors 8 are used to monitor the amount of tension exerted by the angle-adjusting steel cables 6, during the process of adjusting the angle of the lower platform 5 or maintaining the posture of the lower platform 5. Ensure that the tension of the angle adjustment cable 6 is within a certain range to avoid danger. During the driving process, if the value of the tension sensor 8 exceeds the first threshold, the lift motor 7 corresponding to the angle adjustment cable 6 will reduce the speed. , if the value of the tension sensor 8 exceeds the second threshold, the lifting motor 7 corresponding to this angle adjustment cable 6 will stop immediately, and the second threshold is greater than the first threshold.

A CCD camera 9 is provided on the lower surface of the upper platform 3, a target scale 10 is provided on the upper surface of the lower platform 5, and a level 11 is also provided on the lower platform 5; the CCD camera 9, the target scale 10 and the level 11 constitute the components of this application. The above-described swing angle detection device can jointly realize the swing angle detection of the lower platform 5. The level 11 is used to detect the horizontal state of the lower platform 5 and plays an important role in the calibration process of the CCD camera 9; the CCD camera 9 and the target ruler 10 can detect the swing angle of the lower platform 5. The specific process will be introduced in detail later.

The lower surface of the lower platform 5 is provided with a number of T-shaped slots 12 and threaded holes in an array, which can be used to fix special spreaders for clamping hoisted objects. The installation position of the special spreaders can be flexibly selected according to the specific shape and characteristics of the hoisted objects. . Special spreaders can ensure the initial position of the hoisted object.

As shown in Figure 2, the target ruler 10 is in the shape of an isosceles right triangle, with a total of four targets arranged on it. The distance between the targets is known. Three targets are arranged at equal intervals on the hypotenuse, and on each right-angled side There are two targets. Because the angle adjustment accuracy requirements of the lifting spreader are not particularly high, there is no need to set up a particularly large number of target points to increase the accuracy of the solution. However, the focus is on the X-axis direction, Y-axis direction and the lower platform 5. The diagonal directions of the attention to spatial information. The target ruler 10 is made of carbon fiber material, which can effectively reduce the influence of the factory environment temperature on the target ruler and basically eliminate the influence of the thermal expansion coefficient. The target ruler 10 is attached to and fixed on the upper surface of the lower platform 5 through a pressure plate, opposite to the position of the CCD camera 9 . The target ruler 10 has only one fixed point, so that the deformation of the target ruler 10 caused by multiple fixed points can be avoided as much as possible to affect the posture measurement accuracy.

Preferably, at least one target point that is out of the same plane as the four targets on the target scale 10 can be provided to provide more spatial information and improve measurement accuracy.

In the embodiment, the maximum measurement distance of the camera is 1 meter, the resolution of the camera is 1292pixel×964pixel, the pixel size is 3.75μm×3.75μm, and the lens focal length is 3.6mm. The distance between target points is between 10cm-20cm.

The working process of the crane spreader 100 with the swing angle detection device is as follows.

(1) Use a special fixture to fix the object to be hoisted on the lower surface of the lower platform 5; detect the initial horizontal state of the lower platform 5 through the level 11, and adjust the lower platform 5 by driving the angle adjustment cable 6 through the four lifting motors 7 The horizontal state reaches the expected range; in the initial horizontal state, it can provide a reference benchmark for subsequent adjustments.

(2) When the lower platform 5 is horizontal, the CCD camera 9 collects the image of the target ruler 10; according to the parameter requirements of the final assembly of the object to be hoisted, the corresponding lifting displacements of the four angle adjustment cables 6 in this application are calculated (this displacement can be Converted into the number of rotations of the lifting motor 7, this displacement can also be monitored through a displacement sensor when the lifting motor driving angle is adjusted by the steel cable 6).

(3) Referring to Figure 6, the control unit controls the coordinated movement of the four lifting motors 7 to drive the lower platform 5 to rotate around the lower spherical hinge ball head 14; at this time, the four tension sensors 8 provided on the four angle adjustment cables 6 Monitor the tension of the angle adjustment cable 6 (if the value of the tension sensor 8 exceeds the first threshold, the lifting motor 7 corresponding to the angle adjustment cable 6 will reduce the rotation speed. If the value of the tension sensor 8 exceeds the second threshold, then the The lifting motor 7 corresponding to this angle adjustment cable 6 will stop immediately). At the same time, the CCD camera 9 collects images of the target ruler 10 in different postures. The control unit extracts the image of the target ruler 10 and extracts the feature points on it. Calibrate the internal parameters of the CCD camera and solve the pose.

(4) If the error between the calculated posture (i.e., swing angle) and the expected value is within the threshold range, the trolley mechanism drives the object to be hoisted to move to the workpiece for final assembly, which is achieved through the height adjustment mechanism 1 and the rotation mechanism 2 The height of the object to be hoisted and the angle around the vertical direction are adjusted, and the final assembly is finally achieved; if the error between the calculated posture (i.e., the swing angle) and the expected value exceeds the threshold range, the corresponding lifting and lowering of the four angle adjustment cables 6 will be recalculated displacement, and perform step (3).

In step (3), the control unit controls the coordinated movement of the four lifting motors 7. Preferably, it can first control the lifting and lowering of the two angle adjustment cables 6 in one diagonal direction, and then control the two angle adjustment cables 6 in the other diagonal direction. The root angle adjustment steel cable 6 lifts.

The pose calculation algorithm in the above embodiment can use any mature visual analysis algorithm in the existing technology. Regarding the visual pose measurement and resolution algorithm, relevant research has been started as early as the 1980s, using image information to solve the problem. There are many algorithms for calculating spatial position and attitude, especially the monocular visual pose calculation method based on feature points. Those skilled in the art can choose a suitable calculation algorithm based on the actual measurement accuracy and computing power.

The height adjustment mechanism 1 in the above embodiment can be a hydraulic device, a pneumatic device or an electric telescopic device, such as a hydraulic cylinder, a pneumatic cylinder or an electric push rod.

The rotating mechanism 2 in the above embodiment may be an electric turntable.

As shown in Figure 6, the level 11, the four tension sensors 8, and the CCD camera 9 are all electrically connected to the control unit. The control unit will send signals to the height adjustment mechanism 1, the four lifting motors 7, and the rotating mechanism 2 based on sensor signals or external instructions. Control instruction.

The crane spreader 100 with the swing angle detection device in the first embodiment can realize the adjustment of angles and displacements in multiple dimensions by setting the height adjustment mechanism 1, the rotation mechanism 2, the rigid connecting rod 4, and the four angle adjustment cables 6. Efficiently adjust the posture of the object to be hoisted to achieve rapid assembly; through the detection of posture through monocular vision, timely detection of posture can be achieved, and feedback control of the lifting motor can be performed for posture adjustment. Compared with other existing inertial element solutions or other optical angle sensor solutions (such as grating code disks), this swing angle detection solution effectively reduces costs and achieves good application results while meeting accuracy requirements. The principle is simple and intuitive , very suitable for on-site workers, and the hoisting time can be shortened from the original one day to less than half an hour.

Embodiment 2

Compared with the first embodiment, the second embodiment further improves the platform stability of the lower platform 5 .

In the first embodiment, the lower ends of the four angle adjustment cables 6 are respectively connected to the four end corners of the upper surface of the lower platform 5, and their upper ends are connected to the output shafts of the corresponding lifting motors 7 in the upper platform 3. This design facilitates the lifting of the motor. The angle of the lower platform 5 is adjusted through the angle adjustment cable 6, but the stability of the lower platform 5 is poor.

Therefore, in the second embodiment, as shown in Figure 3, a crane spreader 200 with a swing angle detection device is provided with four wire rope guide mechanisms 13 at the lower middle position of the rigid connecting rod 4, and the angle adjustment wire ropes are 6. Pass through the steel cable guide mechanism 13 and then connect it to the output shaft of the corresponding lifting motor 7 in the upper platform 3. This is equivalent to lowering the position of the fixed end of the steel cable, which can effectively improve the stability of the lower platform 5. By limiting Meta-software analysis shows that under the same conditions, if the cable guide mechanism 13 is set at 1/3 to 1/2 of the height of the rigid link 4, the amplitude of the vibration of the lower platform 5 will be reduced by more than half.

The cable guide mechanism 13 can be a guide ring. Preferably, the cable guide mechanism 13 is a guide pulley with a rotating shaft fixed at a lower middle position of the rigid connecting rod 4 .

Preferably, a guide pulley is also provided on the lower surface of the upper platform 3 to adjust the direction of the angle adjustment cable 6 .

The remaining technical solutions in the second embodiment are the same as those in the first embodiment.

Embodiment 3

After the platform stability of the lower platform 5 is improved in the second embodiment, the angle adjustment cable 6 first passes through the cable guide mechanism 13, and then passes through the guide pulley provided on the lower surface of the upper platform 3 to connect to the lifting motor 7, effectively lifting the lower platform 5 platform stability, but the four angle adjustment steel cables 6 converge towards the rigid link 4, which also causes the field of view of the CCD camera to be affected. In order to solve this problem and further improve the integration and reliability of the device, this method has been implemented The technical solution of Example 3.

As shown in Figure 4, a crane spreader 300 with a swing angle detection device includes: a height adjustment mechanism 1, a rotating mechanism 2, an upper platform 3, a rigid connecting rod 4, four angle adjustment cables 6, and four lifting motors 7 , lower platform 5, CCD camera 9, projector 16 and level 11.

The upper end of the height adjustment mechanism 1 is fixedly connected to the lower end of the trolley mechanism of the lifting device. The lower end of the height adjustment mechanism 1 is fixedly connected to the fixed part of the rotating mechanism 2. The rotating part of the rotating mechanism 2 is fixedly connected to the center position of the top surface of the upper platform 3; The center positions of the rigid connecting rod 4 and the upper platform 3 are connected through the upper spherical hinge ball head 15 provided at the upper end of the rigid connecting rod 4. The upper spherical hinge ball head 15 of the rigid connecting rod 4 is built in the upper platform 3, and the lower end of the rigid connecting rod 4 Fixedly connected to the center position of the upper surface of the lower platform 5 , the rigid connecting rod 4 provides a rigid support for the lower platform 5 , and the lower platform 5 can realize rotation angle adjustment through the upper ball hinge ball head 15 .

Both the upper platform 3 and the lower platform 5 are square structures with a certain thickness. Each of the four internal corners of the upper platform 3 is provided with a lifting motor 7; the lower ends of the four angle adjustment cables 6 are respectively connected to the upper surface of the lower platform 5. At the four end corners, four cable guide mechanisms 13 are provided at the lower middle position of the rigid connecting rod 4. The angle adjustment cable 6 passes through the cable guide mechanism 13 and is then connected to the corresponding lifting motor 7 in the upper platform 3. of the output shaft. The four angle adjustment cables 6 can flexibly adjust the angle of the lower platform 5 through the driving of the four lifting motors 7 . The four angle adjustment cables 6 are each provided with a tension sensor 8. The tension sensor 8 is used to monitor the amount of tension received by the angle adjustment cable 6, during the process of adjusting the angle of the lower platform 5 or maintaining the posture of the lower platform 5 Ensure that the tension of the angle adjustment cable 6 is within a certain range to avoid danger. During the driving process, if the value of the tension sensor 8 exceeds the first threshold, the lift motor 7 corresponding to the angle adjustment cable 6 will decrease rotation speed, if the value of the tension sensor 8 exceeds the second threshold, the lifting motor 7 corresponding to this angle adjustment cable 6 will stop immediately, and the second threshold is greater than the first threshold.

Figure 5 shows a schematic structural diagram of the upper spherical hinge structure and the swing angle detection device. A cavity for accommodating the upper ball hinge ball head 15 is formed in the lower part of the upper platform 3. A tapered hole 31 with a larger upper part and a smaller lower part is formed in the lower part of the cavity to facilitate the movement of the rigid connecting rod 4 without interfering with the upper platform 3. Interference occurs; a cylindrical cavity 32 is formed in the upper part of the cavity. In the upper part of the cavity 32, a CCD camera 9 and a projector 16 are fixed on the inside of the upper wall of the upper platform 3. A portion of the top of the upper hinge ball head 15 is cut off to form a target surface 151 parallel to the lower platform 5. The height of the cut-off portion is not greater than 1/4 of the diameter of the sphere. The projector 16 can project target points on the target surface 151.

Since the size of the target surface 151 is small and the projector 16 is used to project the target point on the target surface 151, the fixed deformation of the target ruler and the influence of the thermal expansion coefficient can be effectively avoided, and the target surface 151 is parallel to the lower platform 5 so that The position and posture of the lower platform 5 can be characterized. The CCD camera 9 is set inside the cavity 32, which can effectively avoid interference from the external environment on the CCD camera 9 (such as the obstruction of the angle adjustment cable and external dust pollution, etc.).

A level 11 is also provided on the lower platform 5; the CCD camera 9, the projector 16 and the level 11 constitute the swing angle detection device described in this embodiment, which can jointly realize the swing angle detection of the lower platform 5. The level 11 is used to detect the horizontal state of the lower platform 5 .

The lower surface of the lower platform 5 is provided with a number of T-shaped slots 12 and threaded holes in an array, which can be used to fix special spreaders for clamping hoisted objects. The installation position of the special spreaders can be flexibly selected according to the specific shape and characteristics of the hoisted objects. . Special spreaders can ensure the initial position of the hoisted object.

The working process of the crane spreader 300 with the swing angle detection device is as follows.

(1) Use a special fixture to fix the object to be hoisted on the lower surface of the lower platform 5; detect the initial horizontal state of the lower platform 5 through the level 11, and adjust the lower platform 5 by driving the angle adjustment cable 6 through the four lifting motors 7 The horizontal state reaches the expected range; in the initial horizontal state, it can provide a reference benchmark for subsequent adjustments.

(2) When the lower platform 5 is horizontal, the CCD camera 9 collects the image projected by the projector 16 on the target surface 151; according to the parameter requirements of the final assembly of the object to be hoisted, the corresponding lifting displacements of the four angle adjustment cables 6 are calculated (this can be The displacement amount is converted into the number of rotations of the lifting motor 7, and this displacement amount can also be monitored by the displacement sensor when the lifting motor drive angle adjustment cable 6 is used).

(3) Referring to Figure 6, the control unit controls the coordinated movement of the four lifting motors 7 to drive the lower platform 5 to rotate around the upper spherical hinge ball head 15; at this time, the four tension sensors 8 provided on the four angle adjustment cables 6 Monitor the tension of the angle adjustment cable 6 (if the value of the tension sensor 8 exceeds the first threshold, the lifting motor 7 corresponding to the angle adjustment cable 6 will reduce the rotation speed. If the value of the tension sensor 8 exceeds the second threshold, then the The lifting motor 7 corresponding to this angle adjustment cable 6 will stop immediately). At the same time, the CCD camera 9 collects images of the target surface 151 in different postures. The control unit extracts the image of the target surface 151 and extracts the feature points on it. Calibrate the internal parameters of the CCD camera and solve the pose.

(4) If the error between the calculated posture (i.e., swing angle) and the expected value is within the threshold range, the trolley mechanism drives the object to be hoisted to move to the workpiece for final assembly, which is achieved through the height adjustment mechanism 1 and the rotation mechanism 2 The height of the hoisted object and the angle around the vertical direction are adjusted, and the final assembly is finally completed; if the error between the calculated posture (i.e., the swing angle) and the expected value exceeds the threshold range, the corresponding lifting and lowering of the four angle adjustment cables 6 will be recalculated displacement, and perform step (3).

The height adjustment mechanism 1 in the above embodiment can be a hydraulic device, a pneumatic device or an electric telescopic device, such as a hydraulic cylinder, a pneumatic cylinder or an electric push rod.

The rotating mechanism 2 in the above embodiment may be an electric turntable.

As shown in Figure 6, the level 11, the four tension sensors 8, and the CCD camera 9 are all electrically connected to the control unit. The control unit will send signals to the height adjustment mechanism 1, the four lifting motors 7, and the rotating mechanism 2 based on sensor signals or external instructions. Control instruction. Different from the first embodiment, the projector 16 is also electrically connected to the control unit.

The above embodiments can improve the integration and reliability of the spreader, and have better technical effects than the first two embodiments. The CCD camera in each embodiment is not a limitation on this application, and other suitable types can also be selected. imaging device.

In the pose calculation, theoretically, the larger the size between the target points, the higher the measurement accuracy of the pose. Therefore, in Example 1, the distance between the target points is between 10cm and 20cm, and the target ruler is set larger. It is to improve the measurement accuracy as much as possible if conditions permit, because at this time the angle adjustment cable 6 will not interfere with the camera measurement; and in the second embodiment, when the four angle adjustment cables 6 pass through the cable The guide mechanism 13 seriously interferes with the camera's field of view, and accordingly affects the size of the target ruler. Therefore, although the second embodiment improves the stability of the spreader, it sacrifices part of the accuracy of the pose measurement; and in the third embodiment , this application creatively moves the ball joint ball head from the lower part of the rigid link to the upper part, and sets a target surface 151 parallel to the lower platform 5 on it, so that the projector 16 can project the target point on the target surface 151, Such a design allows pose measurement to be performed in a closed environment, which can effectively avoid interference from the external environment. Moreover, the reduced area of the target surface 151 also reduces its displacement in the depth direction, and the requirements for the camera's depth of field will also be reduced accordingly. The cost can be effectively reduced. Although the final actual pose accuracy is slightly lower than that of Embodiments 1 and 2 (within a difference of 8%), it has great advantages in terms of equipment integration, reliability, and cost control.

The above descriptions are only preferred embodiments of the present application and are not intended to limit the present application. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still make modifications to the foregoing embodiments. Improve the recorded technical solutions, or make equivalent replacements for some of the technical features. Any modifications and equivalent substitutions made within the spirit and principles of this application shall be included in the protection scope of this application.

Claims (7)

1. A crane spreader with a swing angle detection device, which is characterized in that it includes: a height adjustment mechanism, a rotating mechanism, an upper platform, a rigid connecting rod, four angle adjustment cables, four lifting motors, a lower platform, and a CCD camera , target ruler and level; The upper end of the height adjustment mechanism is fixedly connected to the lower end of the trolley mechanism of the lifting device, the lower end of the height adjustment mechanism is fixedly connected to the fixed part of the rotating mechanism, and the rotating part of the rotating mechanism is fixedly connected to the center position of the top surface of the upper platform; the rigid connecting rod The upper end is fixedly connected to the center of the bottom surface of the upper platform. The lower end of the rigid connecting rod is equipped with a lower spherical hinge ball head. The lower spherical hinge ball head at the lower end of the rigid connecting rod is built into the lower platform. The rigid connecting rod passes through the lower spherical hinge ball head. The lower platform provides a rigid support, and the lower platform can realize rotation angle adjustment by relying on the lower ball hinge ball head provided on it; Both the upper platform and the lower platform are square structures. Each of the four inner corners of the upper platform is equipped with a lifting motor; the lower ends of the four angle adjustment cables are respectively connected to the four end corners of the upper surface of the lower platform, and their upper ends are connected to their corresponding The output shaft of the lifting motor in the upper platform and the four angle adjustment cables are equipped with tension sensors. The tension sensors are used to monitor the amount of tension exerted by the angle adjustment cables; during the driving process of the angle adjustment cables, if the tension sensor If the value of the tension sensor exceeds the first threshold, the lift motor corresponding to the angle adjustment cable will reduce the speed. If the value of the tension sensor exceeds the second threshold, the lift motor corresponding to the angle adjustment cable will stop immediately. The second threshold is greater than the first threshold; A CCD camera is provided on the lower surface of the upper platform, a target ruler opposite to the CCD camera is provided on the upper surface of the lower platform, and a level is also provided on the lower platform; the CCD camera, target ruler and level form a swing angle detection device to realize the lower platform Swing angle detection; The lower surface of the lower platform is provided with a number of T-shaped slots and threaded holes in an array, which are used to fix special slings for clamping and hoisting objects. The special slings are used to determine the initial posture of the hoisted objects; The target ruler is an isosceles right triangle with a total of four targets set on it. The distance between the targets is known. Three targets are set at equal intervals on the hypotenuse, and there are two targets on each right-angled side; Four cable guide mechanisms are set at the lower middle part of the rigid connecting rod. The angle adjustment cable passes through the cable guide mechanism and is connected to the output shaft of the corresponding lifting motor in the upper platform; The cable guide mechanism is a guide pulley with the rotating shaft fixed at the lower middle position of the rigid connecting rod; The working process of the crane spreader with swing angle detection device is as follows: (1) Use a special fixture to fix the object to be hoisted on the lower surface of the lower platform; detect the initial horizontal state of the lower platform through a level, and adjust the horizontal state of the lower platform to the expected range by driving the angle-adjusting steel cables driven by four lift motors. ;In the horizontal initial state, it provides a reference benchmark for subsequent adjustments; (2) When the lower platform is horizontal, the CCD camera collects the image of the target ruler; according to the parameter requirements of the final assembly of the object to be hoisted, the corresponding lifting displacements of the four angle adjustment cables are calculated; (3) The control unit controls the coordinated movement of the four lifting motors to drive the lower platform to rotate around the lower ball hinge ball head; four tension sensors set on the four angle adjustment cables monitor the tension of the angle adjustment cables, and at the same time, the CCD The camera collects images of the target ruler in different postures, and the control unit extracts the image of the target ruler, extracts feature points on it, calibrates the internal parameters of the CCD camera and solves the posture; (4) If the error between the calculated pose and the expected value is within the threshold range, the trolley mechanism drives the object to be hoisted to the workpiece for final assembly, and the height and vertical position of the object to be hoisted are realized through the height adjustment mechanism and rotation mechanism. Angle adjustment in the straight direction is performed to finally achieve final assembly; if the error between the calculated pose and the expected value exceeds the threshold range, the corresponding lifting displacements of the four angle adjustment cables are recalculated and step (3) is performed. 2. The crane spreader as claimed in claim 1, characterized in that the height adjustment mechanism is a hydraulic cylinder, a cylinder or an electric push rod. 3. The crane spreader of claim 1, wherein the rotating mechanism is an electric turntable. 4. The crane spreader as claimed in claim 1, characterized in that a guide pulley is provided on the lower surface of the upper platform to adjust the angle adjustment direction of the steel cable. 5. A crane spreader with a swing angle detection device, which is characterized by including: a height adjustment mechanism, a rotating mechanism, an upper platform, a rigid connecting rod, four angle adjustment cables, four lifting motors, a lower platform, and a CCD camera , projector and level; The upper end of the height adjustment mechanism is fixedly connected to the lower end of the trolley mechanism of the lifting device, the lower end of the height adjustment mechanism is fixedly connected to the fixed part of the rotating mechanism, and the rotating part of the rotating mechanism is fixedly connected to the center position of the top surface of the upper platform; the rigid connecting rod is connected to The center position of the upper platform is connected through an upper spherical hinge ball head provided at the upper end of the rigid connecting rod. The upper spherical hinge ball head of the rigid connecting rod is built into the upper platform. The lower end of the rigid connecting rod is fixedly connected to the center position of the upper surface of the lower platform. The rigid connecting rod is The connecting rod provides a rigid support for the lower platform, and the lower platform can adjust the rotation angle through the upper ball hinge ball head; Both the upper platform and the lower platform are square structures. Each of the four internal corners of the upper platform is equipped with a lifting motor; the lower ends of the four angle adjustment cables are respectively connected to the four end corners of the upper surface of the lower platform, and are connected to the rigid connecting rods. Four steel cable guide mechanisms are set at the lower part of the middle. The angle adjustment cables pass through the cable guide mechanisms and are connected to the output shaft of the corresponding lifting motor in the upper platform; the four angle adjustment cables are driven by the four lifting motors. The angle of the lower platform can be flexibly adjusted; the four angle adjustment cables are equipped with tension sensors; A cavity for accommodating the upper ball hinge ball head is formed in the lower part of the upper platform, and a tapered hole with a larger upper and smaller size is formed in the lower part of the cavity; a cylindrical cavity is formed in the upper part of the cavity, and a cylindrical cavity is formed in the lower part of the cavity. On the upper part, a CCD camera and a projector are fixed on the inner side of the upper wall of the upper platform; a part of the top of the upper spherical hinge ball head is cut off to form a target surface parallel to the lower platform. If the height of the cut-off part is not greater than the diameter of the sphere, the projector can be Project target points on the target surface; The CCD camera, projector and level form a swing angle detection device to realize the swing angle detection of the lower platform; The cable guide mechanism is a guide pulley with the rotating shaft fixed at the lower middle position of the rigid connecting rod; The working process of the crane spreader with swing angle detection device is as follows: (1) Use a special fixture to fix the object to be hoisted on the lower surface of the lower platform; detect the initial horizontal state of the lower platform through a level, and adjust the horizontal state of the lower platform to the expected range by driving the angle-adjusting steel cables driven by four lift motors. ;In the horizontal initial state, it provides a reference benchmark for subsequent adjustments; (2) When the lower platform is horizontal, the CCD camera collects the image projected by the projector on the target surface; according to the parameter requirements of the final assembly of the object to be hoisted, the corresponding lifting displacements of the four angle adjustment cables are calculated; (3) The control unit controls the coordinated movement of the four lifting motors to drive the lower platform to rotate around the upper spherical hinge ball head; at this time, the four tension sensors installed on the four angle adjustment cables monitor the tension of the angle adjustment cables, and At the same time, the CCD camera collects images of the target surface in different poses, and the control unit extracts images of the target surface, extracts feature points on it, calibrates the internal parameters of the CCD camera and solves the pose; (4) If the error between the calculated pose and the expected value is within the threshold range, the trolley mechanism drives the object to be hoisted to the workpiece for final assembly, and the height and vertical position of the object to be hoisted are realized through the height adjustment mechanism and rotation mechanism. The angle adjustment in the straight direction is finally completed. If the error between the calculated pose and the expected value exceeds the threshold range, the corresponding lifting displacements of the four angle adjustment cables are recalculated and step (3) is performed. 6. The crane spreader of claim 5, wherein during the driving process, if the value of the tension sensor exceeds the first threshold, the lifting motor corresponding to the angle adjustment cable will operate at a reduced speed. If If the value of the tension sensor exceeds the second threshold, the lifting motor corresponding to this angle adjustment cable will stop immediately, and the second threshold is greater than the first threshold. 7. The crane spreader as claimed in claim 5, characterized in that the lower surface of the lower platform is provided with a number of T-shaped slots and threaded holes in an array for fixing special spreaders for clamping and hoisting objects; special spreaders Used to determine the initial pose of the hoisted object.